<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');
/**
 * CodeIgniter
 *
 * An open source application development framework for PHP 4.3.2 or newer
 *
 * @package		CodeIgniter
 * @author		ExpressionEngine Dev Team
 * @copyright	Copyright (c) 2008 - 2009, EllisLab, Inc.
 * @license		http://codeigniter.com/user_guide/license.html
 * @link		http://codeigniter.com
 * @since		Version 1.0
 * @filesource
 */

// ------------------------------------------------------------------------

/**
 * CodeIgniter Hooks Class
 *
 * Provides a mechanism to extend the base system without hacking.  Most of
 * this class is borrowed from Paul's Extension class in ExpressionEngine.
 *
 * @package		CodeIgniter
 * @subpackage	Libraries
 * @category	Libraries
 * @author		ExpressionEngine Dev Team
 * @link		http://codeigniter.com/user_guide/libraries/encryption.html
 */
class CI_Hooks {

  var $enabled 		= FALSE;
  var $hooks   		= array();
  var $in_progress	= FALSE;

  /**
   * Constructor
   *
   */
  function CI_Hooks() {
    $this->_initialize();
    log_message('debug', "Hooks Class Initialized");
  }

  // --------------------------------------------------------------------

  /**
   * Initialize the Hooks Preferences
   *
   * @access	private
   * @return	void
   */
  function _initialize() {
    $CFG =& load_class('Config');

    // If hooks are not enabled in the config file
    // there is nothing else to do

    if ($CFG->item('enable_hooks') == FALSE) {
      return;
    }

    // Grab the "hooks" definition file.
    // If there are no hooks, we're done.

    @include(APPPATH.'config/hooks'.EXT);

    if ( ! isset($hook) OR ! is_array($hook)) {
      return;
    }

    $this->hooks =& $hook;
    $this->enabled = TRUE;
  }

  // --------------------------------------------------------------------

  /**
   * Call Hook
   *
   * Calls a particular hook
   *
   * @access	private
   * @param	string	the hook name
   * @return	mixed
   */
  function _call_hook($which = '') {
    if ( ! $this->enabled OR ! isset($this->hooks[$which])) {
      return FALSE;
    }

    if (isset($this->hooks[$which][0]) AND is_array($this->hooks[$which][0])) {
      foreach ($this->hooks[$which] as $val) {
        $this->_run_hook($val);
      }
    }
    else {
      $this->_run_hook($this->hooks[$which]);
    }

    return TRUE;
  }

  // --------------------------------------------------------------------

  /**
   * Run Hook
   *
   * Runs a particular hook
   *
   * @access	private
   * @param	array	the hook details
   * @return	bool
   */
  function _run_hook($data) {
    if ( ! is_array($data)) {
      return FALSE;
    }

    // -----------------------------------
    // Safety - Prevents run-away loops
    // -----------------------------------

    // If the script being called happens to have the same
    // hook call within it a loop can happen

    if ($this->in_progress == TRUE) {
      return;
    }

    // -----------------------------------
    // Set file path
    // -----------------------------------

    if ( ! isset($data['filepath']) OR ! isset($data['filename'])) {
      return FALSE;
    }

    $filepath = APPPATH.$data['filepath'].'/'.$data['filename'];

    if ( ! file_exists($filepath)) {
      return FALSE;
    }

    // -----------------------------------
    // Set class/function name
    // -----------------------------------

    $class		= FALSE;
    $function	= FALSE;
    $params		= '';

    if (isset($data['class']) AND $data['class'] != '') {
      $class = $data['class'];
    }

    if (isset($data['function'])) {
      $function = $data['function'];
    }

    if (isset($data['params'])) {
      $params = $data['params'];
    }

    if ($class === FALSE AND $function === FALSE) {
      return FALSE;
    }

    // -----------------------------------
    // Set the in_progress flag
    // -----------------------------------

    $this->in_progress = TRUE;

    // -----------------------------------
    // Call the requested class and/or function
    // -----------------------------------

    if ($class !== FALSE) {
      if ( ! class_exists($class)) {
        require($filepath);
      }

      $HOOK = new $class;
      $HOOK->$function($params);
    }
    else {
      if ( ! function_exists($function)) {
        require($filepath);
      }

      $function($params);
    }

    $this->in_progress = FALSE;
    return TRUE;
  }

}

// END CI_Hooks class

/* End of file Hooks.php */
/* Location: ./system/libraries/Hooks.php */